It's something we've all heard before - 'the red card changed the game completely' and, sure enough, up came two cases in two days of where a red card decision did just that.
At the Etihad on Tuesday night, Martin Demichelis brought down Lionel Messi to give away a penalty and received a red card, with Messi converting the resulting spot-kick. The same happened to Wojciech Szczesny for bringing down Arjen Robben on Wednesday night at the Emirates.
Despite David Alaba missing the resulting penalty for Bayern Munich, the argument still stands. Should football change its rules by not giving both a red card and a penalty?
These types of matches are the highest level and are won and lost by the slightest of margins. So to be faced with a penalty and a red card changes the game completely and effectively ruins the game as a contest.
Manchester City's game against Barcelona had developed into an enthralling battle of the two best attacking teams in Europe pitting their wits against each other. Any hopes of a goalfest we were all hoping for between the two teams were obliterated when Jonas Eriksson awarded the penalty (albeit controversially) and sent off culprit Demichelis following his late challenge on Messi.
As soon as Messi dispatched home on 54 minutes, everyone could predict the pattern of the game that would take place for the remainder of the match.
Barcelona get ball, keep ball, pass, pass, pass, keep ball.
Manchester City offered a few threats on the counter attack, but in reality they were always vulnerable against a Barcelona side who didn't really look like they were worried at any stage after playing against 10 men.
Tiring Manchester City conceded a second late on with Dani Alves looking to put the tie out of reach for the home side.
Take Arsenal's game against Bayern Munich, now. The first 20 minutes promised much, with both teams having chances to open the scoring.
Toni Kroos' 25-yard effort was heading for the top corner until a fine Szczesny save and surprise starter Yaya Sanogo tested Manuel Neuer before the German goalkeeper saved Mesut Ozil's tame penalty.
It all went wrong for the Gunners when Robben went down in the penalty area following contact from Szczesny which earned him a red card.
Arsenal had 12% of the possession in the second half, completing only 62 passes to Bayern's 508 - that says it all.
Arsenal, like Manchester City, tired in the closing stages of the game because of their numerical disadvantage and also lost the game 2-0.
The Champions League knockout stages are all about ties like Arsenal v Bayern Munich and Manchester City vs Barcelona, where fans want to see end-to-end, action packed ties or fascinating tactical tight battles between Europe's elite.
As soon as a player is sent off for something as simple as a mistimed challenge which would only be a yellow card anywhere else on the pitch and with the chance of goal via a penalty kick it ends the game as a spectacle, with the ensuing action becoming a drab affair.
If there is a violent challenge in the penalty area that constitutes necessary action being taken, then by all means give the player his marching orders. However, both of these challenges were not malicious, just simply mistimed. Maybe a rethink of the rules is in order to keep the game more entertaining.
Perhaps offering players - maybe the captain, a choice to either send the player off and resume play from their own half, or to be awarded the penalty? That decision alone would make for some great talking points and show how much of a tactical mind the captains of a football team do have.
Would they be allowed to communicate with their manager at the time? It would would also be fascinating to see the reaction of a home support if they disagreed with their captain's decision.
A penalty or having to play the rest of the game with 10 men is more than a harsh enough sanction for a team to face without having the other punishment to face as well. This would revolutionise the game.
It would get the crowd involved trying to influence player decisions, take less pressure off the referees and keep the game more entertaining.
What's not to like?
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